/* This file is part of the OWL API.
 * The contents of this file are subject to the LGPL License, Version 3.0.
 * Copyright 2014, The University of Manchester
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Alternatively, the contents of this file may be used under the terms of the Apache License, Version 2.0 in which case, the provisions of the Apache License Version 2.0 are applicable instead of those above.
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */
package org.semanticweb.owlapi6.utility;

import static org.semanticweb.owlapi6.utilities.OWLAPIPreconditions.checkNotNull;

import java.util.HashMap;
import java.util.Map;

import org.semanticweb.owlapi6.model.IRI;
import org.semanticweb.owlapi6.model.OWLDataFactory;
import org.semanticweb.owlapi6.model.OWLDatatype;
import org.semanticweb.owlapi6.model.OWLEntity;

/**
 * Provides an entity URI conversion strategy which converts entity URIs to a common base and
 * alpha-numeric fragment. The fragment is of the form An, where n is an integer (starting at 1),
 * and A is a string which depends on the type of entity:
 * <ul>
 * <li>For classes: A = "C"</li>
 * <li>For object properties: A = "op"</li>
 * <li>For data properties: A = "dp"</li>
 * <li>For individuals: A = "i"</li>
 * </ul>
 *
 * @author Matthew Horridge, The University Of Manchester, Bio-Health Informatics Group
 * @since 2.2.0
 */
public class OWLEntityTinyURIConversionStrategy implements OWLEntityURIConverterStrategy {

    /**
     * default base.
     */
    public static final String DEFAULT_BASE = "http://tinyname.org#";
    private final String base;
    private final Map<OWLEntity, IRI> entityNameMap = new HashMap<>();
    private final OWLEntityFragmentProvider fragmentProvider = new OWLEntityFragmentProvider();
    private OWLDataFactory df;

    /**
     * Constructs an entity URI converter strategy, where the base of the generated URIs corresponds
     * to the value specified by the DEFAULT_BASE constant.
     * 
     * @param df data factory
     */
    public OWLEntityTinyURIConversionStrategy(OWLDataFactory df) {
        this(DEFAULT_BASE, df);
    }

    /**
     * Constructs an entity URI converter strategy, where the specified base is used for the base of
     * the URIs generated by the generator.
     *
     * @param base The base to be used.
     * @param df data factory
     */
    public OWLEntityTinyURIConversionStrategy(String base, OWLDataFactory df) {
        this.base = checkNotNull(base, "base cannot be null");
        this.df = df;
    }

    @Override
    public IRI getConvertedIRI(OWLEntity entity) {
        IRI iri = entityNameMap.get(entity);
        if (iri != null) {
            return iri;
        }
        if (entity instanceof OWLDatatype) {
            return entity.getIRI();
        }
        String name = fragmentProvider.getName(entity);
        iri = df.getIRI(base, name);
        entityNameMap.put(entity, iri);
        return iri;
    }
}
